An analysis of context-aware user interfaces shows that adaptation mechanisms have a cost-benefit trade-off for usability. Unpredictable autonomous interface adaptations can easily reduce a system’s usability. To reduce this negative effect of adaptive behaviour, we have attempted to help users building adequate mental models of such systems. A user support concept was developed and applied to a context-aware mobile device with an adaptive user interface. The approach was evaluated with users and as expected, the user support improved ease of use, but unexpectedly it reduced learnability. This shows that an increase of ease of use can be realised without actually improving the user’s mental model of adaptive systems. Categories and Subject Descriptors H.5.2 [Information Interfaces and Presentation]: User Interfaces – Auditory (non-speech) feedback, Ergonomics, Evaluation/methodology, Graphical user interfaces, Input devices and strategies, Prototyping, Voice I/O. General Terms M...
Tim F. Paymans, Jasper Lindenberg, Mark A. Neerinc